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E Dabelsteen

Publications and source records attributed to E Dabelsteen.

At least 109 records · Page 6Linked to original sources
PubMed1987

Blood group ABO and Lewis antigen expression during neoplastic progression of human urothelium. Immunohistochemical study of type 1 chain structures.

The deletion of blood group ABO antigen expression in bladder carcinoma has attracted attention because of its potential as a prognostic parameter. Based on recently produced monoclonal antibodies against blood group antigens, it has become possible to elucidate the carcinoma-associated modulation of these antigens at a molecular level. In this study we have used a panel of monoclonal antibodies (H, Lea, Leb, A, ALeb) that are specific to type 1 chain structures. By the use of an immunohistochemical method, the histologic and cytologic location of these antigens in the urothelium was studied in 25 biopsies from transitional cell carcinomas and compared to 21 previously examined normal biopsies. Urothelial blood group reactivity was compared to Lewis and secretor status. The authors found a series of events associated with neoplastic progression of noninvasive urothelium: a disruption of the orderly stratification of blood group antigens in different cell layers; cytostructural relocation of cytoplasmic antigens to the cell surface; loss of correlation between urothelial blood group antigens and secretor status; and gradual deletion of antigens. In the invasive tissue these events were followed by a total deletion of A and H isoantigens and uniform expression of Lewis b and sialyted Lewis a antigen. These findings indicate that there is a complex modulation of blood group antigen biosynthesis associated with the neoplastic progression of the human urothelium.

ABO Blood-Group System↗
PubMed1987

Connective tissue influences on the expression of epithelial cell-surface antigens.

Adult mice were found to show regional variation in the epithelial expression of some molecules of the blood-group antigen series. To investigate connective tissue influences on such differences, heterotypic recombinants of epithelia and connective tissues from various regions were prepared and examined using monoclonal antibodies directed against bloodgroup antigens H and Ley. The results indicate that epithelia may maintain a preexisting regionally specific pattern following recombination but that, in some recombinant matches, the connective tissue is capable of signalling redirection of the pattern of expression towards that typical of the epithelium with which it is normally associated.

Animals↗
PubMed1987

Blood group ABO and Lewis antigens in fetal and normal adult bladder urothelium: immunohistochemical study of type 1 chain structures.

Five monoclonal antibodies specific for structural variants of type 1 chain blood group antigens (H, Lea, Leb, A, ALeb) were used to study the distribution of these particular antigens in normal bladder urothelium. The urothelium samples were taken from seven human fetuses (aged seven to 21 weeks) and 19 adults. The adults were blood group A and O individuals, and their antigen expression was compared to ABO, secretor, and erythrocyte Lewis status. Detailed data on the histological location of the antigens were obtained by means of immunohistochemical methods. In fetuses expression of Lewis a and A antigens was stage-dependent, whereas the Lewis b and H antigens were consistently present at all stages. In adults the urothelial blood group antigen expression seemed to be correlated to ABO and secretor status, but not to erythrocyte Lewis type. Secretors expressed primarily ABO isoantigens on their cell membranes, whereas non-secretors (four individuals) expressed inappropriate Lewis antigens. Examination of the histological distribution of the antigens showed results different from earlier examined epithelia. In adult bladder urothelium from A secretors, only the most complex antigens (Leb, A, ALeb) were present in the basal germinative cell layer, whereas the luminal umbrella cell layer expressed both these antigens and showed a unique expression of less complex precursor antigens (H, Lea), as well as sialylated Lewis a antigens.

ABO Blood-Group System↗
PubMed1987

Herpes simplex virus-induced changes of the keratin type intermediate filament in rat epithelial cells.

Herpes simplex virus type 1 (HSV-1) infection of human fibroblast cells grown in culture induces reorganization of the cytoskeleton fibrillar structures. Normal transport and insertion of HSV glycoproteins into the plasma membrane of the cells depend on the integrity of the microtubules. The natural host cells for HSV are epithelial cells, and an epithelial cell line established from rat palate was used in the present study. The effect of virus on the structure of the intermediate filaments and especially on the keratin proteins was studied. Two-dimensional gel electrophoresis of total cell extracts identified in uninfected cells two major acidic keratin proteins with apparent molecular weights of 44,000 (44K) and 48K (pI 5.45 to 5.30, 5.50 to 5.35). A new keratin protein of 46K (pI 5.40 to 5.25) appeared in infected cells between 8 h and 12 h post-infection. Pulse-chase experiments identified the 46K protein as a processed form of the 48K keratin component, which was also cleaved in uninfected cells grown in the presence of cycloheximide. Partial proteolysis of the 46K and 48K keratins with Staphylococcus aureus V8 protease showed that the 48K and the 46K proteins differed in only one oligopeptide. The significance of the changed keratin composition of HSV-infected cells is discussed.

Animals↗
PubMed1987

Angiogenic activity of malignant oral epithelial cells: a preliminary study.

We investigated the angiogenetic capacity of normal and malignant oral epithelial cells by intradermal injection of cells into nude mice. Cells investigated: 1) a tumorigenic cell line from rat palate; 2) a non-tumorigenic epithelial cell line from rat palate; 3) cells from second passage of rat palate epithelium explant cultures; 4) cells from epidermis of neonatal mice. A 0.1 ml suspension containing 10(5) epithelial cells was injected into the flank region. Mice were killed 8 days later to evaluate angiogenesis. Under a dissection microscope, the number of vessels in the skin adjacent to the injection site was counted. The tumorigenic cell line demonstrated the strongest angiogenetic capacity and the non-tumorigenic cell line was more angiogenic than any of the other non-tumorigenic cell types. The greater angiogenic activity of neoplastic oral epithelial cells may be a useful feature in the evaluation of oral malignant development.

Animals↗
PubMed1987

Effects of irradiation with dental light curing units on Langerhans cells in human stratified epithelium in heterotransplanted skin.

Grafts of human skin on nude mice were subjected to a single dose of either 2 1/2 min or 4 min of radiation from two different commercial dental light curing units with emission mainly in the visible light spectrum but also with a small fraction of UV-A light. Seventy-two hours after exposure the tissue was examined for presence of Langerhans cells using monoclonal antibody OKT6 double layer immunofluorescence staining. Epithelial hyperplasia and reduced reactivities for OKT6 were seen after 2 1/2 min exposure. After 4 min of exposure OKT6 positive cells were completely absent from the epithelium. The results indicate that emission from dental light curing units can affect Langerhans cells in human epithelium and could thus modify the local immunologic response.

Animals↗
PubMed1987

Immunomicroscopic localization of aminopeptidase N in the pig enterocyte. Implications for the route of intracellular transport.

The subcellular localization of aminopeptidase N (EC 3.4.11.2) in the pig enterocyte was investigated by immunofluorescence and immunoelectron microscopy (immunogold staining). By indirect immunofluorescence on either frozen or paraffin-embedded sections, a very intense staining in the microvillar membrane and a weak intracellular staining was demonstrated. No staining was detected in the basolateral membrane. Likewise, the immunogold labelling on Epon-embedded sections was concentrated in the microvillar membrane, whereas the basolateral membrane did not contain significant amounts of labelling. Labelling was demonstrated in the Golgi apparatus and in a minor fraction of the intracellular smooth vesicles positioned between the Golgi apparatus and the microvillar membrane. These observations are compatible with the view that newly synthesized aminopeptidase N is delivered directly to the microvillar membrane by smooth vesicles having a diameter about 70 to 100 nm and does not pass the basolateral membrane on its way to the brush border membrane.

Aminopeptidases↗
PubMed1987

The tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) accelerates expression of differentiation markers in cultures of rat palatal epithelial cells.

Cultures of rat palatal epithelium grown on collagen rafts were treated with different doses of the potent tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). Sections from biopsies taken 1, 6, 24, and 48 hr after the addition of TPA were examined for the localization of staining by blood group antigen H antibody and antikeratin antibody AE1. In contrast to control cultures, where antigen H was seen exclusively at the cell membranes of the second and third cell layer, several antigen H-positive cells, some appearing in groups, were found in the basal cell layer of TPA-treated specimens. Staining for keratins with the AE1 antikeratin antibody showed no staining of basal cells but only suprabasal cells in controls, whereas several cells of the basal cell layer of TPA-treated cultures stained positively with this antibody. The results support the theory that TPA, by forcing a part of the basal cell population to terminal differentiation, strongly affects the composition of the basal cell population.

Animals↗
PubMed1986

Differentiation-dependent expression of keratins in human oral epithelia.

The polypeptide composition of epithelial keratins varies with the state of differentiation. The epithelia lining the human oral cavity show regional variations in their histology. In the present study, paired samples of nonkeratinized buccal epithelium and keratinized hard palate epithelium were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and by immunoblots with monoclonal antibodies AE1, AE2, and AE3, and results were correlated with immunofluorescence staining of tissue sections of the same samples. Keratins from hard palate (Mr 67K, 63-65K, 58K, 56.5K, 56K, 50K, 48K) and epidermis (Mr 67K, 63-65K, 58K, 56.5K, 50K) were similar to each other but distinctly different from those of buccal epithelium (major bands of Mr 52K and 59K, minor bands of 50K and 58K). The immunoblot analysis further indicated the similarity of hard palate and epidermal keratins, in contrast to those of buccal epithelium. Each oral tissue expressed keratins of the type I (AE1, acidic) subfamily and type II (AE3, basic) subfamily. In tissue sections, the predominant staining pattern for nonkeratinized buccal epithelium was: AE1, positive in the basal layer; AE2, negative; AE3, positive in all layers. In contrast, the staining pattern for keratinized palatal epithelium was: AE1 and AE2, positive in the suprabasal layers; AE3, positive in all layers. Strong suprabasal AE1 staining in palate may be related to the presence of the 48K keratin. Some buccal samples showed an alternate staining pattern of spotty suprabasal staining with AE1 and AE2 which was correlated with the expression of the 56.5K and 63-67K keratins, as well as filaggrin. These results suggest differentiation-specific expression of the keratins and show immunologically detectable variation in the apparently normal differentiation pattern of nonkeratinized buccal epithelium.

Antibodies, Monoclonal↗
PubMed1986

Cell surface carbohydrate changes during embryonic and fetal skin development.

Monoclonal antibodies to four type 2 chain carbohydrate antigens were used for immunohistochemical studies of embryonic and fetal skin. The antibodies detected N-acetyllactosamine and 3 fucosyl substitutes of this, blood group antigen H, Lex, and Ley. Periderm consistently stained for N-acetyllactosamine, Lex and Ley. The H antigen showed a variable and weak expression on peridermal cells from day 57 to day 84 estimated gestation age (EGA). After this period the H antigen was no longer expressed at peridermal cells. In the epidermis, N-acetyllactosamine was present on all cells until the age of 15 weeks EGA. After this period N-acetyllactosamine could only be demonstrated on basal cells after treatment with neuraminidase, indicating a masking of N-acetyllactosamine by sialic acid. The H antigen could not be demonstrated in the epithelium before 14 weeks EGA. At this time it appeared on spinous and granular cells in the epithelium. Lex stained both basal cells and intermediate cells positively, until keratinization around week 20 EGA. Ley is never expressed on basal cells. It is weakly expressed by intermediate cells from week 14 EGA. Our study demonstrates that N-acetyllactosamine is maximally expressed at the early stages of development, but may later be modified either by sialylation or fucosylation into blood group H or Lex, or by Ley substances, respectively. The orderly and well-defined changes observed during skin differentiation are in agreement with other studies, which have demonstrated the existence of chemically defined cell surface changes accompanying cell differentiation.

ABO Blood-Group System↗
PubMed1986

Keratin proteins in human oral mucosa.

We have examined the keratin proteins in normal human oral mucosa from 6 different regions including hard palate, buccal mucosa, tongue, gingiva and floor of the mouth. Urea-dithiothreitol extracts of EDTA separated epithelia were analysed by SDS-PAGE and immunoblotting. Eight samples from each region were investigated and showed very little individual variation in the keratin profile on Coomasie Blue-stained gels. The keratinizing hard palate and gingiva expressed identical patterns and resembled the pattern of epidermis from the flank region. The normally non-keratinizing buccal mucosa and the mucosa of the floor of the mouth expressed polypeptides distinctly different from those of the keratinizing epithelia and lacked the high molecular weight keratins. The dorsal surface of the tongue and the commissure region showed a pattern intermediate between keratinizing and non-keratinizing epithelia. The greater sensitivity of the immunoblotting technique revealed that the non-keratinizing epithelia synthesized one of the high molecular polypeptides and that the tongue produced all the bands found in keratinizing epithelia, but in very small quantities. There are, thus, distinct differences in the keratin expression of oral epithelia which are related to the pattern of keratinization assessed histologically.

Adult↗
PubMed1986

The distribution of blood group antigens in experimentally produced carcinomas of rat palate.

It has been shown previously that rat oral epithelia express antigens cross-reacting with antibodies against human blood group antigen B and its structural precursor, the H antigen (Type 2 chain). In the present study we investigated the expression of these antigens in malignant changes in the rat palate induced by a chemical carcinogen (4NQO). The H antigen, normally expressed on spinous cells in rats, was absent in malignant epithelium, whereas staining for the B antigen, normally expressed on basal cells, was variable. These changes are equivalent to those seen in human squamous cell carcinomas. The blood group antigen staining pattern in experimentally produced verrucous carcinomas showed an almost normal blood group antigen expression. This may have diagnostic significance. Localized areas of hyperplastic palatal epithelium with slight dysplasia revealed loss of H antigen and the presence of B antigen in suprabasal strata equivalent to the pattern seen in human premalignant epithelium. We conclude from these findings, that the rat model is well suited to study changes in cell surface carbohydrates during chemical carcinogenesis.

4-Nitroquinoline-1-oxide↗
PubMed1986

Staining patterns of rodent squamous epithelia by monoclonal anti-keratin antibodies.

Anti-keratin staining patterns were examined by immunofluorescence in the epidermis, oral mucosa and forestomach of rats and mice by monoclonal antibodies AE1 and AE2. In contrast to human tissues enzymatic pretreatment of sections was necessary even when fresh-frozen tissue was used, suggesting masking of the antigens in vivo. AE1 stained the cytoplasm of spinous cells in most epithelia, whereas basal cell staining varied. AE2 showed suprabasal cytoplasmic staining in epidermis, forestomach and palate, whereas the other epithelia were stained only in keratohyalin granules and membranes of cornified cells. In some epithelia a small number of irregularly distributed basal cells stained positive with AE2, indicating heterogeneity in the basal cell compartment. Thus, the anti-keratin staining pattern varies both regionally and, as earlier shown in human epithelium, with the stage of maturation of cells within a given epithelium. The present study provides a basis for further studies of epithelial differentiation during normal and pathologic development.

Animals↗
PubMed1986

Incompatible A antigen expressed in tumors of blood group O individuals: immunochemical, immunohistologic, and enzymatic characterization.

Monofucosyl type 1 chain A (type 1 Aa) and difucosyl type 1 chain A (ALeb), but not other types of A antigens, have been detected by application of carrier type-specific monoclonal anti-A antibodies (AH21 and HH3) in colonic tumors of blood group O individuals. An A-transferase activity (UDP-Gal-NAc:H-alpha-GalNAc transferase) was demonstrated in the extract of one of the O tumors expressing A antigen. The incidence of A antigen expression in O tumors was found to be two out of 15 cases, based on TLC immunostaining of glycolipid extracts, and five out of 50 cases, based on immunofluorescent staining of tumors with AH21 and HH3 antibodies.

ABO Blood-Group System↗
PubMed1985

A differential diagnostic approach to the symptomatology of acute dental pain.

Seventy-four patients with acute pulpitis, apical periodontitis, marginal periodontitis, or pulpoperiodontitis were examined. A series of symptoms and signs was registered. Diagnostic specificities and sensitivities were calculated, and thirteen variables were subjected to discriminant analysis and log-linear multiway contingency table analysis. Pulpoperiodonitis was found inseparable from pulpitis on the basis of the registered symptoms and signs. Several symptoms and signs previously believed to have differential diagnostic power were found insignificant. The following combination of symptoms and signs yielded a correct diagnosis in 82.1% of the cases: constant pain, tenderness to temperature changes, "the tooth feels extruded," impaired mouth opening, tenderness to palpation in apical area, and mobility.

Dental Pulp↗